* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

body {
    background: linear-gradient(135deg, #1a2980 0%, #26d0ce 100%);
    color: #333;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.login-container {
    width: 100%;
    max-width: 520px;
    padding: 16px;
}

.login-card {
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.3);
    overflow: hidden;
    animation: fadeInUp 0.8s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.login-header {
    padding: 35px 30px 25px;
    background: linear-gradient(to right, #4285f4, #34a853);
    color: white;
    text-align: center;
    position: relative;
}

.logo-circle {
    width: 90px;
    height: 90px;
    background: white;
    border-radius: 50%;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    animation: pulse 2s infinite;
}

.logo-circle i {
    font-size: 3.5rem;
    background: linear-gradient(to right, #4285f4, #34a853);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.login-header h1 {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 8px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.login-header p {
    font-size: 1.1rem;
    opacity: 0.9;
    max-width: 300px;
    margin: 0 auto;
    line-height: 1.5;
}

.login-body {
    padding: 30px;
}

.form-group {
    margin-bottom: 25px;
    position: relative;
}

.form-group label {
    display: block;
    margin-bottom: 10px;
    font-weight: 600;
    color: #2c3e50;
    font-size: 1.05rem;
    display: flex;
    align-items: center;
}

.form-group label i {
    margin-right: 10px;
    color: #4285f4;
    font-size: 1.1rem;
    width: 20px;
}

.form-group input {
    width: 100%;
    padding: 15px 20px 15px 50px;
    border: 1px solid #ddd;
    border-radius: 12px;
    font-size: 1.05rem;
    background: #f8fafc;
    transition: all 0.3s;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05) inset;
}

.form-group input:focus {
    border-color: #4d90fe;
    box-shadow: 0 0 0 3px rgba(66, 133, 244, 0.2), 0 2px 5px rgba(0,0,0,0.05) inset;
    outline: none;
    background: white;
}

.input-icon {
    position: absolute;
    left: 18px;
    top: 43px;
    color: #888;
    font-size: 1.2rem;
}

.remember-forgot {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    font-size: 0.95rem;
}

.remember {
    display: flex;
    align-items: center;
}

.remember input {
    margin-right: 8px;
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.forgot-password {
    color: #4285f4;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
}

.forgot-password:hover {
    color: #1a2980;
    text-decoration: underline;
}

.btn {
    padding: 16px;
    border: none;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: 100%;
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
}

.btn-login {
    background: linear-gradient(to right, #4285f4, #34a853);
    color: white;
    margin-bottom: 20px;
    position: relative;
    overflow: hidden;
}

.btn-login:hover {
    transform: translateY(-3px);
    box-shadow: 0 7px 20px rgba(0,0,0,0.2);
}

.btn-login:active {
    transform: translateY(-1px);
}

.btn-login::after {
    content: "";
    position: absolute;
    top: -50%;
    left: -60%;
    width: 20px;
    height: 200%;
    background: rgba(255, 255, 255, 0.3);
    transform: rotate(30deg);
    transition: all 0.8s;
}

.btn-login:hover::after {
    left: 140%;
}

.social-login {
    text-align: center;
    margin-top: 25px;
    position: relative;
}

.social-login::before {
    content: "";
    position: absolute;
    top: 12px;
    left: 0;
    right: 0;
    height: 1px;
    background: #eee;
    z-index: 1;
}

.social-login span {
    display: inline-block;
    background: white;
    padding: 0 15px;
    position: relative;
    z-index: 2;
    color: #666;
    font-size: 0.95rem;
}

.social-icons {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 20px;
}

.social-icon {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    color: white;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 4px 10px rgba(0,0,0,0.15);
}

.social-icon:hover {
    transform: translateY(-5px);
    box-shadow: 0 7px 15px rgba(0,0,0,0.2);
}

.facebook {
    background: linear-gradient(to right, #3b5998, #486ab4);
}

.google {
    background: linear-gradient(to right, #ea4335, #fbbc05);
}

.github {
    background: linear-gradient(to right, #333, #6e5494);
}

.login-footer {
    text-align: center;
    padding: 25px;
    color: rgba(255, 255, 255, 0.85);
    font-size: 1rem;
}

.login-footer a {
    color: white;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
}

.login-footer a:hover {
    text-decoration: underline;
}

/* 响应式设计 */
@media (max-width: 480px) {
    .login-card {
        border-radius: 15px;
    }

    .login-header {
        padding: 25px 20px 20px;
    }

    .logo-circle {
        width: 80px;
        height: 80px;
    }

    .login-header h1 {
        font-size: 1.8rem;
    }

    .login-body {
        padding: 25px 20px;
    }

    .form-group input {
        padding: 14px 15px 14px 45px;
    }

    .input-icon {
        left: 15px;
        top: 40px;
        font-size: 1.1rem;
    }
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes pulse {
    0% { transform: scale(1); box-shadow: 0 5px 15px rgba(0,0,0,0.2); }
    50% { transform: scale(1.05); box-shadow: 0 8px 25px rgba(0,0,0,0.3); }
    100% { transform: scale(1); box-shadow: 0 5px 15px rgba(0,0,0,0.2); }
}

@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-15px); }
    100% { transform: translateY(0px); }
}

.floating {
    position: absolute;
    z-index: -1;
    opacity: 0.15;
    animation: float 8s ease-in-out infinite;
}

.floating:nth-child(1) {
    top: 10%;
    left: 10%;
    font-size: 5rem;
    animation-delay: 0s;
}

.floating:nth-child(2) {
    top: 20%;
    right: 15%;
    font-size: 4rem;
    animation-delay: -2s;
}

.floating:nth-child(3) {
    bottom: 30%;
    left: 15%;
    font-size: 6rem;
    animation-delay: -5s;
}

.floating:nth-child(4) {
    bottom: 20%;
    right: 10%;
    font-size: 3.5rem;
    animation-delay: -3s;
}